exampleTileMap.go

gistfile1.txt

// Copyright 2018 The Ebiten Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package main

import (
	"image"
	"image/color"

	"github.com/hajimehoshi/ebiten/v2"
	"github.com/hajimehoshi/ebiten/v2/ebitenutil"
	"github.com/hajimehoshi/ebiten/v2/inpututil"
)

type Game struct {
	layers  [][]int
	Tilemap *ebiten.Image
}

func NewGame() *Game {
	g := &Game{
		layers: [][]int{
			{
				9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
				9, 0, 0, 0, 0, 0, 0, 0, 0, 9,
				9, 0, 0, 0, 0, 0, 0, 0, 0, 9,
				9, 0, 0, 0, 0, 0, 0, 0, 0, 9,
				9, 0, 0, 0, 0, 0, 0, 0, 0, 9,
				9, 0, 0, 0, 0, 0, 0, 0, 0, 9,
				9, 0, 0, 0, 0, 0, 0, 0, 0, 9,
				9, 0, 0, 0, 0, 0, 0, 0, 0, 9,
				9, 0, 0, 0, 0, 0, 0, 0, 0, 9,
				9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
			},
			{
				0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
				0, 0, 0, 260, 0, 0, 0, 0, 0, 0,
			},
		},
	}

	tilemapImage, _, _ := ebitenutil.NewImageFromFile("monochrome_tilemap_packed.png")

	g.Tilemap = tilemapImage

	return g
}

const (
	screenWidth  = 160
	screenHeight = 160
)

const (
	tileSize = 16
)

func (g *Game) Update() error {

	if inpututil.IsKeyJustPressed(ebiten.KeyF4) {
		ebiten.SetFullscreen(!ebiten.IsFullscreen())
	}

	if inpututil.IsKeyJustPressed(ebiten.KeyEscape) {
		return ebiten.Termination
	}

	return nil
}

func (g *Game) Draw(screen *ebiten.Image) {

	screen.Fill(color.Black)
	w := g.Tilemap.Bounds().Dx()
	tileXCount := w / tileSize

	const xCount = screenWidth / tileSize

	for _, l := range g.layers {

		for i, t := range l {

			// Discard 0's so drawing second layers don't overwrite previous layers
			if t == 0 {
				continue
			}

			op := &ebiten.DrawImageOptions{}
			op.GeoM.Translate(float64((i%xCount)*tileSize), float64((i/xCount)*tileSize))

			sx := (t % tileXCount) * tileSize
			sy := (t / tileXCount) * tileSize
			screen.DrawImage(g.Tilemap.SubImage(image.Rect(sx, sy, sx+tileSize, sy+tileSize)).(*ebiten.Image), op)

		}

	}

}

func (g *Game) Layout(w, h int) (int, int) {
	return screenWidth, screenHeight
}

func main() {

	if err := ebiten.RunGame(NewGame()); err != nil {
		panic(err)
	}

}